Rocky Mountain Spotted Fever

Rocky Mountain Spotted fever, Typhus fever, or Rickettsiosis

Rickettsia rickettsii (bacterial)

Gram negative rod, obligate intracellular parasite

Ticks and other animals (rodents)

Epidermis

Arthropod vector Tick bite (wood or dog)

5-14 days

Bacteria multiply at the site of tick bite and then invade endothelia cells lining the blood vessels resulting in systemic inflammation and tissue damage (obstructed/damaged blood vessels cant bring blood to region causing tissue death-neucrosis)

Possible damage at site of tick bite, fever, headache, loss of appetite, nausea, vomiting, stomach pain, myalgia, RASH (Maculopapular)

affects 85-90%, 2-5 days after fever, flat red lesions less than 1 cm (nonitchy), starts at wrists and ankles

Tissue Necrosis- digit/limb loss, hearing loss, paralysis, mental disability, kidney failure, heart failure. Death- 0.5% of cases (treated), 20-80% (untreated), 5x more likely in young children

Avoid ticks- treat clothes with 0.5% permethrin

Antibiotics- begin treatment within 5 days of first symptoms to decrease the chance of fatal complications, Tetracycline, Doxycycline, Chloramphenicol